Continue rotating a circular image with mouseDragged where it was left off

[jeremydouglass]

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Creating sectors in a rotating circular image

Hi, I have a circular image that rotates on mouseDragged and the image has various letters around the circle, when I drag the image to a certain position, one of the letters goes on top of a box indicating i want to write that letter, but I’m having problems coding this last part. I don’t know how to create and identify each sector of the image when in rotation. Any ideas?